I. Field of the Invention
The present invention relates generally to vehicle windshield defroster systems.
II. Description of Related Art
The defrosting and deicing of automotive vehicles' front windshields has been typically performed by conventional warm air defrosters. These warm air defrosters are heated by the heat from the coolant system which flows through a defroster core. Air fans then circulate air across the core and up to the inside surface of the windshield.
A primary disadvantage of these previously known warm air windshield defroster systems is that the overall time required to completely defrost and/or deice a front windshield is very lengthy. This relatively long time required to completely defrost and deice the front windshield results from two factors. First, the engine coolant for the internal combustion engine in the automotive vehicle must become sufficiently heated to heat the air used to defrost the front windshield. Depending upon the weather conditions, it may require a minute or two for the engine coolant to become sufficiently heated to heat the air used to defrost the front windshield.
The second, and more important, factor impacting upon the time required to defrost the front windshield using a hot air defrost system is that the heat transfer between the air and the front windshield, as well as the heat conductance through the windshield and to the ice on the front windshield, is very inefficient. Indeed, in very cold conditions and with substantial ice buildup on the front windshield, the actual defrost/deice operation on the front windshield may require 15-30 minutes. Such a long time delay to defrost/deice the front windshield not only wastes time, but also engine fuel.
In order to provide quicker defrosting/deicing of the front windshield, there have been previously known systems which heat the washer fluid for the front windshield. Many of these previously known heated washer fluid systems have utilized an electric heater fluidly connected to the windshield washer system in order to heat the windshield washer fluid. However, these previously known electrically heated windshield washer systems suffer from a number of disadvantages.
First, both the construction and installation of the electrically heated washer fluid systems are relatively high thus adding a significant cost to the overall vehicle. The automotive industry is particularly competitive so that the addition of a relatively expensive heater system for the washer fluid is economically infeasible.
A second and more significant disadvantage of these previously known electrically heated windshield washer systems is that such systems have been known to malfunction in operation. Indeed, malfunction of the heater system can result in engine compartment fires and resulting damage to the automotive vehicle.
The present invention provides a windshield washer fluid heater which overcomes the above mentioned disadvantages of the previously known systems.